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working on my 12 now and a couple of clarifications to your post:
The gross weight increase is probably from Charlie Center @ Crosswinds. The dogleg extended baggage is a different stc, probably from Ron Sullivan. Still not clear if the upper baggage is part of Charlies GW increase.
the Gullwing door and modification to lower the door base makes getting in and out of the 12 easier. That is another STC from Crosswinds.
you may also want to look at the pa-18 seat mod with the battery under the front seat, but that gets pricey pretty quickly. An Atlee Dodge STC
i alos opted for the cub crafters fuel system stc to get rid of the header tanks, and put in a fuel valve with on/off/both as well as left and right.

The 12 type certificate (or maybe it is the original drawings) shows the header tanks being an option, so no STC is needed to remove them. The Dakota Cub fuel selector and the sight guages are both very high quality and a great addition, as I recall cheaper than Cub crafters and they come with an STC.

Hi Wayne. Good to hear from you. I ran across your name recently at home while looking for something else. Glad to see you are progressing on your project. I look forward to following you along. I haven't been on .org too much lately. I need to get back to this site. This will be a good excuse to do so. Take care.

The 12 type certificate (or maybe it is the original drawings) shows the header tanks being an option, so no STC is needed to remove them. The Dakota Cub fuel selector and the sight guages are both very high quality and a great addition, as I recall cheaper than Cub crafters and they come with an STC.

My 12 doesn't have a header tank or the front STC'd lines.

I've thought about putting the front lines in. But who in hell is going to be doing hard maneuvering when you're running out of gas?

Early in 2005, I had located an IA who was knowledgeable about Cubs, and, just as important, was local to me. In Feb/March, '05, he picked up my fuselage and brought it to his shop. Keep in mind that Univair did not yet have their jig ready for producing fuselages. One of the first things we attacked was the crushed right doorpost. The plane had landed upside down after it broke loose during a windstorm two owners ago. It bent the spars and lift struts, smashed all of the wing ribs and fuel tanks, broke the flywheel and twisted the fuselage. Much was repaired by the PO to some extent.

We cut the door post and jacked the fuselage internally to square things up. The right front wing attach point was quite a bit lower than it should have been. I can't imagine how stall/spins would be in this configuration.

We installed a Sullivan extended baggage, X brace, -14 cathedral, -18 landing gear tabs and cabane, float fittings, elevator controls, repaired the jackscrew tower, sleeved the tailspring mount, new door trim, replaced the doorpost and a few other tubes in the cockpit area, -18 trim system, boxed the tail, replaced the D window frames, replaced some of the piper channel for the boot cowl and false cowl and missing pieces for the skylight.

The fuselage was then blasted and checked for perforated tubing.

The fuselage returned to the hangar in September, 05. My wallet was also quite a bit lighter too, so the trip back to the airport was easier. I treated the bare metal with "A Must for Rust" recommended by Kent White for preventing flash rust from forming on bare metal. This gave it a blue-ish tint. When I got it back to the hangar, it was time for more evaluation. That is what you do when you don't know what the next step should be.

Next step? Maybe work on the wing until I can figure out what to do next to the fuselage. We had not really addressed the condition of the longerons in the way of the jackscrew tower and tailpost. They were not perforated, having been replaced after the wind storm, but I thought they were still a mess.

You are quite right... time for an update. As I write this, I have to dig back into the dusty, cobwebbed recesses of my mind.

I moved the fuselage to my garage so I could spend more dwell time on it. If you remember from my early posts, the plane had been blown over in a wind storm in it's previous life. The wing tie-downs broke and the tail held. When it went over, it landed inverted hard enough that the flywheel/starter ring broke on impact. The wing tops were stove in and the fuel tanks were flattened, making their capacity closer to 9 gallons.

All of this damage had been repaired (after a fashion) and the plane returned to service (sort of) prior to me purchasing it.

With it now residing in my garage, I was able to evaluate it frequently. I purchased a set of ribs and fuel tanks from Dakota Cub. I also purchased spars to replace the ones on the left wing, which the PO had patched by putting two doublers on the web inboard of the lift struts. My IA talked me into installing flaps, so I purchased the flaps and kit from Dakota Cub. I also upgraded the landing gear to SC gear. I found a local 290-D2 for a good price ( false economy) that needed "just a bit of work" to make well.

I happened by the Univair booth at OSH and discovered that they were selling repair sections for the fuselage on 12s now. I ordered and received the "short" section, which included about 8' of longeron forward of the tailpost.

Now, to find someone that had a -12 jig and the capabilities to weld it on and assure that the rest of the fuselage had been returned to square.

I loaded the fuselage into the truck early one morning and set out for the shop. Driving around Minneapolis during the morning rush with 10' of extended load woke up a few drivers, I suspect.

Approximately eight months passed before the fuselage made it into the jig. And then, it was discovered that the tailpost was off plumb by about 5 degrees. Univair was contacted and they exhibited OUTSTANDING customer service by shipping a new one and accepting the other one by return freight. Thank you Jim.

A month or two later, I took delivery of the fuselage.

In the interim, I retired from my day (and night) job and purchased a hangar at the ANE airport and met Darrel Starr, Windonhisnose and a bunch of the SC.org folks who reside there and around the area. The hangar was an empty shell of a pole barn. If I was to be able to work on the plane during the winters, it would need to be insulated and heated.

Next up: the rest of the modifications, hangar updates and what have I been doing since I got the fuselage back in 2012

The fuselage never ended up in a jig. It was attached to a "table" made up of two I beams welded together and ground flat and level to 0.030" end to end and diagonally.

The work was done at Jay's shop in Brainerd, Javron Inc. It happened at a bad time for scheduling. He was in the middle of building his new shop for manufacturing Cub airframes and there was not enough room to set up the -12 jig in his old shop.

The table was a compromise but I am confident the fuselage is as straight as it will ever get. He did a great job on it and it was worth the wait.

Is this project still ongoing? THANK YOU for posting all the pictures!! This has really helped me to see under the skin of the PA-12 and helped to understand mine!! I'm currently wondering how to get access to some of the stuff that's under the outer layer of fabric (over the stringers) and outside the frame fabric itself in the cockpit area, for example fuel switches, trim assembly, fuel pipes etc.

Question: can I just cut holes in the inner cockpit fabric, for example at port rear, covering the trim cables etc, or is this fabric area part of the overall "stretched and stresed" fabric and therefore any holes should be contained within glued on rings etc?

.
Question: can I just cut holes in the inner cockpit fabric, for example at port rear, covering the trim cables etc, or is this fabric area part of the overall "stretched and stresed" fabric and therefore any holes should be contained within glued on rings etc?

you could remove all of the interior if you wanted to... not structural...

Wow. 13 years and untold thousands of dollars in mods. Looks like it could be a nice one when you " getter done". Hope it turns out for ya! Your a much braver man than me........ And have the patience of
Jobe.
Wishing the very best on this massive project!
Best of luck
E

I've just looked at the pics from my Mac and not my iPhone and there's loads more pics than the phone app shows and I can see there's a LOT of work gone into these!!!!!! They look EVEN more great!!!! Top work!!

Yes, I am still plugging away at it. I installed a PA-18 seat and removed the truss. I am installing a seaplane door (right side only) and made one from cheap 3/4" square aluminum to get the dimensions and swing correct. Also to work out the hinge attachment. The new door frame was made from 6061 3/4" aluminum with rounded corners. I am currently working on a latch for it.

I made templates for all of the interior panels except for the one behind the left D window. I also have the templates made for the lower luggage compartment.

I need to mount the wing so I can get the flaps rigged so I began working on the left wing. All hardware was removed, cleaned up and painted or powder coated. New ribs, spars, ailerons, flaps, leading edges, bows and fuel tanks (Dakota Cub) and fasteners.

It is now January, 2019. Progress has been glacial, but ongoing. Last entry was beginning work on the wing to settle some alignment questions with the fuselage and control cables.

I built a simple table to work on the wings. I leveled one end and used diagonal crossing strings to align the other end. I had the new spars alodined at a place in Minneapolis that does light poles and large pieces of architectural trim.

You can see the " table" in the left side of the picture here, supporting the spars. Just a piece of plywood screwed to the legs. A piece of osb ties the other end to this one.

I followed the wing assembly procedures that came with the Dakota Cub rib STC.

Dakota Cub listed the location for the ribs in their procedures. The installation of their fuel tanks requires moving some ribs and compression struts and installing a brace tube in the tank bay.

I ran into an interference issue with the tank and compression strut just outboard of the tank bay.

The new strut supplied with the tank kit uses bolts to hold it together. The original Piper used rivets. I took the bolts out of the strut first and turned them around so the head was toward the tank (this picture) but still, I wanted more space. I replaced this strut with the one from the end of the wing (original Piper) and resolved the problem.

I am using the Sullivan STC for flap installation. There are a number of issues related to the drawings and dimensions for this STC. The issues have been discussed many times on this site.

I assembled the flap hinges and aileron hinges and hung the flap and aileron to see how different the issue would be on this plane. I used super glue to temporarily fasten the bellcrank bracket to tape I put on the spar.

I established where the control cables entered the wing and made a cardboard template I taped to the root rib.
The green strings are the routing for the aileron controls and the orange electrical wire is where the flap control winds up. There were also issues regarding the strap locations for
the fuel tank supports. The one you see here (green) has to miss the bellcrank bracket and the wing root attach bracket on the forward spar.

I played around with moving the bellcrank up and down a bit.

I used a small piece of baling wire to see how far I would need to deflect the control cables to clear the flap pushrod and bellcrank.

I also had to move the rib outboard about one inch to clear the bellcrank. If the bellcrank is moved lower than it is in the right most picture above, it contacts the flap hinge arm instead of the stop.
At this time, the hole is drilled for the flap hinge bracket. NOT where the STC calls out, but the spar print from the Northland cd.
Still have to get a location for the flap return springs. Think it is Mike S. who recommends two springs on each flap.

One of the newer flap STC diagrams shows a bracket used to keep the aileron balance cable off the flap pushrod. Many folks here argue that is a high drag and wear point for the cable. I agree.
I plan on using a small pulley to divert the cable. The pulley will mount to the rib adjacent to the bellcrank.

a bracket used to keep the aileron balance cable off the flap pushrod. Many folks here argue that is a high drag and wear point for the cable. I agree.

I had to install something to deflect the aileron cable from the flap mechanism in my -12. I used a nylon fairlead, though with a little bit of trepidation. I did some calculations for the lateral and frictional forces between fairlead and cable and determined that the friction would be small. In practice, I was happy to find that it works just fine - my ailerons are smooth with very little friction discernible at the stick, including in flight.

Exactly the same story with mine. The fairlead caused no perceptible change in stick feel. If I remember correctly, the interconnect cable was rubbing the flap return spring slightly. The deflection induced by the fairlead is very small.

Maybe not relevant but....... one of the fairleads was missing in the aileron circuit of my PA-12, Iíve only had the plane 9 months so donít know how long itís been missing, but the aileron cable sized hole it was sawing through the mounting bracket was VERY scary!!!

PA-12 Build

Originally Posted by Philly5G

Maybe not relevant but....... one of the fairleads was missing in the aileron circuit of my PA-12, Iíve only had the plane 9 months so donít know how long itís been missing, but the aileron cable sized hole it was sawing through the mounting bracket was VERY scary!!!

Fitting the replacement meant cutting another access hole and a LOT of struggling to get the locking ring on............

The other day I needed to install a circle clip on a fairlead in an un-handy place. I got a pair of spreader pliers with the small pins used for drilled circle clips, put them inside the fairlead clip and Voila! on it went. Gonna use them all the time now. even in a "good" place they are a pain to install with needle nose pliers or something similar.

PA-12 Build

Originally Posted by Hyrdflyr

The other day I needed to install a circle clip on a fairlead in an un-handy place. I got a pair of spreader pliers with the small pins used for drilled circle clips, put them inside the fairlead clip and Voila! on it went. Gonna use them all the time now. even in a "good" place they are a pain to install with needle nose pliers or something similar.

Shiny side up!

Well done!!!! We tried this, but couldnít get the circlip pliers on to the locking ring because of the access situation BRILLIANT you had better luck